Release of VIC.4.1.2.m

---

***** Description of changes from VIC 4.1.2.l to VIC 4.1.2.m *****

Bug Fixes:

Fixed negative liquid soil moisture for bare soil conditions

Files Affected:

runoff.c

Description:

Previously, runoff() only checked whether total (liquid+ice) soil
moisture was > residual moisture, but not whether liquid soil moisture
was positive. In some cases, in the bare soil tile, liquid soil moisture
could occasionally go negative. This has been fixed by adding a check on
liquid soil moisture to runoff().