Did anyone teach the 5 Solas before Luther?

There were multiple people called "proto-Protestants", referring to those who taught reformation ideas prior to Luther, the most famous of these are:

• John Wycliffe (14th century)
• Jan Hus (14-15th centuries)
• Girolamo Savonarola (15th century)
• Peter Waldo (12th century)

Some lesser-known ones are:

• Petr Chelčický (15th century)
• Arnold of Brescia (12th century)
• Claudius of Turin (9th century)
• Wessel Gansfort (15th century)
• Johann Ruchrat von Wesel (15th century)
• Johannes von Goch (15th century)

There are a number of other theologians and groups with similar ideas, Martin Luther himself pointed to many of them as proofs that his views weren't new. 

John Wycliffe is known for translating the bible into English, opposing the power of the pope and opposing transubstantiation. Jan Hus largely followed what John Wycliffe taught, however still being closer to Catholicism. 

Renerius Saccho gave us a list of Waldensian beliefs, which included: condemnation of clerical celibacy, rejection of transubstantiation, the papacy, infant baptism and perhaps implied as to have rejected baptismal regeneration. 

Girolamo Savonarola was closer to Catholicism; he accepted the pope as having universal jurisdiction but denied his infallibility and taught the pope may be opposed. His views of justification also appear to have foreshadowed Protestant views, the following quotes come from Girolamo Savonarola:

 "I preach the regeneration of the Church, taking the Scriptures as my sole guide." 

"It is untrue that God's grace is obtained by pre-existing works of merit as though works and deserts were the cause of predestination. On the contrary, these are the result of predestination. Tell me, Peter; tell me, O Magdalene, wherefore are ye in paradise? Confess that not by your own merits have ye obtained salvation, but by the goodness of God"

"the Pope may command me to do something that contravenes the law of Christian love or the Gospel. But, if he did so command, I would say to him, thou art no shepherd. Not the Roman Church, but thou errest Who are the fat kine of Bashan on the mountains of Samaria? I say they are the courtesans of Italy and Rome. Or, are there none? A thousand are too few for Rome, 10,000, 12,000, 14,000 are too few for Rome. Prepare thyself, O Rome, for great will be thy punishments"  

- "Philip Schaff: History of the Christian Church, Volume VI: The Middle Ages. A.D. 1294-1517 - Christian Classics Ethereal Library

Petr Chelčický had a strong belief in sola scriptura, seeing concepts such as purgatory as "inventions of the Antichrist". However, Petr Chelčický had some views not taught by most Protestant reformers such as pacifism and Christian Anarchism.

Wessel Gansfort criticized indulgences and rejected Catholic concepts of the sacraments.