chore(travis): do not use EGLIBC Option

We're using FILIBXX and not affected by eglibc bugs anymore.
chore(travis): add static build on travis-ci
chore(cmake): OSX doesn't support static binary; check it in cmake
fix(tools/proofcheck/checker): use marctan instead of matan

close #20.
fix(opensmt): fix math function names(arcsin => asin)

We allow both of arcsin and asin for smt2 formula. But internally, we
only use asin (atan, atan2, matan, etc).
minor fix on readme etc
fix(tools/proofchecker/checker): fix math functions(asin,acos,etc)
fix(tools/proofcheck/checker/lexer.mll): update hexlit regex
benchmark(PTC): remove
fix(tools): make smt2 separate module
chore(tools): update Makefile
feat(tools/smt2_stat): add extract_nonlinear_func
benchmark(hybrid_systems/bouncing_ball): fix bouncing_ball.drh to be infix-form
fix(tools/proofcheck/checker/lexer.mll): add support "inf" symbol
fix(tools/smt2_stat): consider Pow(e, 0.5) as "sqrt" function
doc(tools/flyspeck_code): update README
feat(tools/smt2_stat): add print_infix_formula
chore(travis): update secure keys
doc(README.md): use shield.io icon for builds
chore(travis): install cmake and automake for OSX build