[testcases_2-2] moved the sample testcases for 2-2 to c1i/

[testcases_1-3] added the test cases for the Lab1-3

[Lab2-2 c1i_ref] v3.2 fixed global const array length bug; fixed the unary const int float conversion bug.

[Lab2-2 c1i_ref] v3.1 fixed global array int float conversion bugs.

[FAQ.md] fixed the TOC of FAQ.md

[faq] update FAQ

[Lab2-2 c1i_ref] v3.0 fixed global int float conversion bugs.

Merge branch 'master' of github.com:ustc-compiler/2018fall

[HW]added HW10-1

[Lab2-2 c1i_ref] fixed var_def_stmt int float conversion for non-array non-global

[Lab2-2 c1i_ref] fixed lval_is_result_int

[Lab2-2 c1i_ref] fixed inpuFloat

[Lab2-2 c1i_ref] fixed array index bug; fixed var_def_stmt_syntax int float bug.

[Lab2-2 testcases] fixed the 06_fib testcase.

[c1i ref] added the statically linked reference implementation for c1i_ref